As per the documentation, pt-table-checksum is a tool to perform online replication consistency checks by executing checksum queries on the master, which produces different results on replicas that are inconsistent with the master.

The master and each slave insert checksums into the percona.checksums table, and these are later compared for differences. It’s fairly obvious that the checksums need to be determined independently on each node, and so these inserts must be replicated as STATEMENT and not ROW. Otherwise, the slaves would just insert the same checksum as the master and not calculate it independently.

The tool only requires

binlog_format=STATEMENT

  for its own session. It sets this itself on the master, but will error if this isn’t already set on each slave node. The …